Katsuki is a boy who met Misae Sagara many years ago. Misae encourages Katsuki to recover when he is still in his wheelchair. Their meeting leads to the event in Misae's path. Katsuki finds her again and wants to thank her by granting her wish.
He finds out that he is a cat who was kept by the real Katsuki in the Hospital. Before dying, the real Katsuki asked the cat to grant Misae a wish. Misae's one wish was for Katsuki (the cat) to stay by her side and to always love her. But, he loses his human form and goes back to being a cat. Many years later, after Misae returns back the town, he meets up with her again as a cat. She takes him in, and he keeps his promise of granting her wish.